System and method for efficiently preparing taurine

ABSTRACT

The present disclosure provides a system for efficiently preparing taurine, including: a solution storage unit configured to store a solution containing alkali metal taurinate, the solution being prepared by an ethylene oxide process; an ion exchange unit including at least one ion exchange resin column each configured to be activated by a first activation manner or a second activation manner independently, the first activation manner using sulfurous acid for activation to obtain alkali metal bisulfate and taurine, and the second activation manner using sulfuric acid for activation to obtain alkali metal sulfate and taurine; and a dispensing unit connected to the solution storage unit and the ion exchange unit respectively, and configured to adjust an amount of a solution conveyed from the solution storage unit to each of the at least one ion exchange resin column in the ion exchange unit.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of International applicationNo. PCT/CN2021/107399, filed on Jul. 20, 2021, which claims priority toand benefits of Chinese Patent Application No. 202110322108.2 filedbefore the China National Intellectual Property Administration on Mar.25, 2021, the entire contents of which are incorporated herein byreference.

TECHNICAL FIELD

The present disclosure relates to the field of chemical engineering, andspecifically relates to a system and method for efficiently preparingtaurine.

BACKGROUND

Taurine is a special sulfur-containing amino acid, which hasanti-inflammatory, antipyretic, analgesic, anticonvulsant, and bloodpressure-lowering effects as a drug. As a health product, it also hasgood promotion effects on brain development, nerve conduction,improvement of visual function, and calcium absorption of infants andchildren.

China, as the world's largest taurine production base, contributes about5 tons of taurine raw materials prepared by an ethylene oxide processannually. The ethylene oxide process for preparing taurine includes thefollowing three steps.

Ethylene oxide is reacted with alkali metal bisulfate to prepare alkalimetal isethionate.

The alkali metal isethionate is reacted with ammonia under alkalineconditions to prepare an alkali metal taurinate. In the reactionprocess, excessive ammonia is required. Therefore, redundant ammonianeeds to be removed by a flash vaporization and evaporation step afterthe reaction is completed, and the solution obtained after evaporationis called as evaporated solution.

Alkali metal ions in the alkali metal taurinate are replaced withhydrogen ions under acidic conditions so as to prepare taurine.

However, the existing production process of taurine is complicated andinefficient. Especially, in the continuous production process, a largenumber of intermediate products will be produced, and a lot of waterwill be consumed, causing the waste of resources. Therefore, there is aneed for developing a novel taurine preparation method.

SUMMARY

Commonly used methods for acidizing alkali metal taurinate include asulfuric acid neutralization method, which produces sulfate, anelectrolytic method and an ion exchange method, which do not producesulfate, etc. Although the ion exchange method, which does not producesulfate, is provided in the related art, the inventors have found thatthe method wastes a lot of water and other resources because the ionexchange process requires many tedious steps such as washing ionexchange columns with water, and diluting materials before the materialsare input into the ion exchange columns. In addition, alkali metalbisulfite as a byproduct produced in the ion exchange process will befurther recycled and reused in the hydroxylation process. However, inthe continuous production process, an intermediate material is inputinto an ion exchange system directly without being separated. Therefore,alkali metal ions in alkali metal taurinate are transformed into alkalimetal bisulfite by an ion resin, and alkali metal ions contained in thealkali for providing an alkaline environment in the ammonolysis reactionprocess are also transformed into alkali metal bisulfite. As onemolecule of ethylene oxide only consumes one molecule of alkali metalbisulfite, alkali metal ions in the whole system are unbalanced. Inorder to achieve the balance of alkali metal ions, theoretically a partof an alkali metal bisulfite solution can be collected and sold.However, the alkali metal bisulfite solution outputted from the ionexchange system contains some impurities and does not have a qualityrequired for selling. Therefore, in order to solve the above problem,the present disclosure provides an efficient taurine preparation systemand method.

In a first aspect, the present disclosure proposes a system forefficiently preparing taurine. According to embodiments of the presentdisclosure, the system includes: a solution storage unit configured tostore a solution containing alkali metal taurinate, the solution beingprepared by an ethylene oxide process; an ion exchange unit including atleast one ion exchange resin column each configured to be activatedindependently by a first activation manner or a second activationmanner, the first activation manner using sulfurous acid for activationto obtain alkali metal bisulfite and taurine, and the second activationmanner using sulfuric acid for activation to obtain alkali metal sulfateand taurine; and a dispensing unit connected to the solution storageunit and the ion exchange unit, the dispensing unit being configured toadjust an amount of the solution conveyed from the solution storage unitto each of the at least one ion exchange resin column in the ionexchange unit. The system according to the embodiments of the presentdisclosure can control the balance of alkali metal ions in the system ina continuous production process of taurine. Reaction materials includingethylene oxide and alkali metal bisulfite react to produce alkali metaltaurinate, the obtained alkali metal taurinate can be acidized intotaurine in the ion exchange unit, the ion exchange resin columns in theion exchange unit can be activated by multiple activation manners, thefirst activation manner uses sulfurous acid for activation so as toobtain alkali metal bisulfite and taurine, and the second activationmanner uses sulfuric acid for activation so as to obtain alkali metalsulfate and taurine. In addition, in order to increase the acidity of asulfurous acid solution serving as an activating reagent, the sulfurousacid solution also contains alkali metal bisulfite. It can be known fromthe chemical formulas, alkali metal bisulfite corresponds to finallyproduced taurine in a ratio of 1:1. Moreover, at the neutralizationreaction step, the produced taurine corresponds to the produced alkalimetal ions in a ratio of 1:1. When the ion exchange unit is activated bythe first activation manner, the first activating reagent containsalkali metal bisulfite, and alkali metal ions in alkali metal taurinatewill be also transformed into alkali metal bisulfite in the activationprocess. In addition, an ammonolysis reaction needs to be performedunder alkaline conditions, so that residual alkali metal ions in thesystem will be also transformed into alkali metal bisulfite after theammonolysis reaction is completed. Therefore, excessive alkali metalbisulfite will be produced. By introducing the second activation mannerusing sulfuric acid as an activating reagent, the excessive alkali metalions produced by the first activation manner can be depleted, and thusthe excessive alkali metal ions are concentrated and collected as alkalimetal sulfate finally to achieve the balance of the alkali metal ions.The system according to the embodiments of the present disclosure iswell designed and suitable for achieving the balance of alkali metalions in the continuous mass production without requiring for an extraproduction line for solving the problem of excessive alkali metal ions,and can achieve the balance of alkali metal ions in the productionprocess of taurine, thereby improving the production efficiency oftaurine while saving cost.

According to embodiments of the present disclosure, the system canfurther include at least one of the following additional technicalfeatures.

According to the embodiments of the present disclosure, the systemfurther includes an activating solution change unit connected to each ofthe at least one ion exchange resin column and configured to adjust anactivation manner of the ion exchange resin column. The inventors havefound that if the ion exchange resin column is continuously activatedwith an alkali metal bisulfite solution in which sulfur dioxide isdissolved in the continuous taurine production process, the ion exchangeresin column will be damaged, and the service life of the ion exchangeresin column will be reduced; and if the ion exchange resin column isintermittently activated with sulfuric acid, the service life of the ionexchange resin column can be prolonged, and the production efficiencycan be improved. The activating solution change unit is a unit forchanging an activation manner performed on an ion exchange resin column.Under the action of the unit, an activation manner performed on an ionexchange resin column can be changed from the sulfurous acid activationmanner to the sulfuric acid activation manner, or changed from thesulfuric acid activation manner to the sulfurous acid activation manner.

According to the embodiments of the present disclosure, the systemfurther includes an alkali metal ion concentration detection moduleconnected to an inlet and an outlet of the ion exchange resin column.The alkali metal ion concentration detection module is adapted toindependently detect a concentration of alkali metal ions in an inputsolution of the ion exchange resin column and a concentration of alkalimetal ions in an output solution of the ion exchange resin column. Boththe input solution and the output solution contain alkali metaltaurinate. The alkali metal ion concentration detection module isconnected to the activating solution change unit to allow the activatingsolution change unit to adjust the activation manner of the ion exchangeresin column based on a detection result of the alkali metal ionconcentration detection module. According to the embodiments of thepresent disclosure, the alkali metal ion concentration detection modulecan accurately determine the concentrations of alkali metal ions in aninput solution and in an output solution of each ion exchange resincolumn, and the state of service of each ion exchange resin column isjudged according to the comparison results, so as to guide theactivating solution change unit to change an activation manner from thesulfurous acid activation manner to the sulfuric acid activation manner,or from the sulfuric acid activation manner to the sulfurous acidactivation manner.

According to the embodiments of the present disclosure, the dispensingunit is configured to adjust an amount of the solution conveyed from thesolution storage unit to each of the at least one ion exchange resincolumn independently. The amount of the solution inputted into the atleast one ion exchange resin column treated by the first activationmanner is 60 wt % to 95 wt % of a total amount of the solution in thesolution storage unit. The amount of the solution inputted into the atleast one ion exchange resin column treated by the second activationmanner is 5 wt % to 40 wt % of the total amount of the solution in thesolution storage unit. According to the embodiments of the presentdisclosure, the amount of the solution inputted into the at least oneion exchange resin column treated by the second activation manner is 5wt %, 10 wt %, 15 wt %, 20 wt %, 25 wt %, 30 wt %, 35 wt % or 40 wt % ofthe total amount of the solution in the solution storage unit. Uponextensive studies, the inventors have found that in the productionprocess of taurine with the system of the present disclosure, extrastrong alkali is added in the ammonolysis reaction process to adjust apH value of the reaction system, and a small part of the strong alkalifor adjusting the pH value will consume some active groups in a resin inthe ion exchange process. If the ion exchange resin column is activatedwith sulfurous acid, one metal ion is displaced with one sulfurous acidto form an alkali metal salt, and one alkali metal salt cancorrespondingly produce one taurine molecule. Thus, if the ion exchangeresin column is activated with sulfurous acid that is produced bydissolving sulfur dioxide with alkali metal bisulfite, excessive alkalimetal bisulfite is present in the production system, a part of thealkali metal bisulfite cannot be recycled and reused, and then excessivealkali metal ions are present in the production system. In order tosolve this problem, a redundant alkali metal bisulfite solution needs tobe disposed. However, the direct sewage disposal is high in cost and lowin efficiency; and if an evaporation and concentration process isadopted, sodium bisulfite, sodium sulfite, etc. are unstable, theresulting salt is unsaleable because of its high levels of impurities,causing the waste of materials. By extensive studies and a large numberof experimental designs, the inventors have found that if the ionexchange resin columns activated by the first activation manner and thesecond activation manner are used to produce taurine from an evaporatedsolution at the same time, during the activation of the ion exchangeresin columns with sulfuric acid, a part of alkali metal ions can betransformed into alkali metal sulfate that belongs to strong alkalisalts, and the alkali metal sulfate can be directly concentrated byevaporation to form a pure product that can be sold or used. Thedisposal method is simple and saves cost and resources.

According to the embodiments of the present disclosure, a ratio of theamount of the solution inputted into the at least one ion exchange resincolumn treated by the first activation manner to the amount of thesolution inputted into the at least one ion exchange resin columntreated by the second activation manner ranges from (3:2) to (19:1).

According to the embodiments of the present disclosure, the activatingsolution change unit is configured to change, in response to theconcentration of alkali metal ions in the output solution of the ionexchange resin column that is being treated by the first activationmanner being greater than 60% of the concentration of alkali metal ionsin the input solution of the ion exchange resin column, the activationmanner of the ion exchange resin column to the second activation manner,and change, in response to the concentration of alkali metal ions in theoutput solution being smaller than or equal to 5% of the concentrationof alkali metal ions in the input solution, the activation manner of theion exchange resin column to the first activation manner. According tothe embodiments of the present disclosure, when the concentration ofalkali metal ions in the output solution is greater than or equal to 60%of the concentration of alkali metal ions in the input solution, itindicates that the ion exchange resin column is not in a good servicecondition, because excessive alkali metal ions are present in the ionexchange resin column, ion exchange performed on alkali metal taurinateis inefficient, the activation manner performed on the ion exchangeresin column needs to be changed, and the ion exchange resin columnneeds to be activated with sulfuric acid. When the concentration ofalkali metal ions in the output solution is smaller than or equal to 5%of the concentration of alkali metal ions in the input solution, itindicates that the ion exchange resin column is in a recovered state andcan be further activated with sulfurous acid (an alkali metal bisulfitesolution in which sulfur dioxide is dissolved). The efficiency ofactivation with sulfurous acid is higher, which is beneficial to theefficient preparation of taurine in the continuous production process.

According to the embodiments of the present disclosure, the systemfurther includes: a solution allocation module connected to a bottom ofeach of the at least one ion exchange resin column, and configured toinput an alkali metal bisulfite solution into the ion exchange resincolumn from bottom to top before the ion exchange resin column istreated by the first activation manner, and input an alkali metalsulfate solution into the ion exchange resin column from bottom to topbefore the ion exchange resin column is treated by the second activationmanner. Upon extensive studies, the inventors have found that treatmentof an ion exchange resin column with an alkali metal salt solution frombottom to top before the ion exchange resin column is activated with astrong acid solution can improve the efficiency of subsequent activationof the ion exchange resin column, and reduce the activation time.

According to the embodiments of the present disclosure, the sulfurousacid used by the first activation manner is obtained by dissolvingsulfur dioxide in an alkali metal bisulfite solution having aconcentration from 25 wt % to 50 wt %. According to the embodiments ofthe present disclosure, an activating reagent used by the firstactivation manner is different from an activating reagent used by thesecond activation manner. The first activation manner mainly usessulfurous acid for activation. Sulfur dioxide is dissolved in an alkalimetal bisulfite solution to increase the solubility of sulfur dioxide soas to produce the sulfurous acid for activation by the first activationmanner. The inventors have found that if the concentration of the alkalimetal bisulfite solution is 25 wt % to 50 wt %, the resulting solutionhas a good activation effect on an ion exchange resin column, theactivation time is short, and the efficiency is high.

According to the embodiments of the present disclosure, the secondactivation manner including activating the ion exchange resin columnusing sulfuric acid at a concentration smaller than or equal to 25 wt %,preferably smaller than or equal to 23 wt %. According to theembodiments of the present disclosure, efficient activation of the ionexchange resin column can be achieved by the second activation mannerusing sulfuric acid at a concentration smaller than or equal to 25 wt %.Upon extensive studies, the inventors have found that in the continuousproduction process of taurine, if an ion exchange resin column iscontinuously activated with an alkali metal bisulfite solution in whichsulfur dioxide is dissolved, the ion exchange resin column will bedamaged, causing reduction of the exchange efficiency of the ionexchange resin column, shortening the service life, increasing theproduction cost, etc. However, compared with activation with sulfuricacid only, activation of the ion exchange resin column with sulfurousacid has a lower cost. Thus, in the continuous production process oftaurine, the ion exchange resin column can be mainly activated withsulfurous acid, and changed to be activated with sulfuric acid accordingto the condition of the ion exchange resin column, which can efficientlyimprove the exchange efficiency, prolong the service life of the ionexchange resin column, improve the production efficiency, and reduce theproduction cost.

According to the embodiments of the present disclosure, the systemfurther includes: a reaction unit connected to the solution storage unitand configured to prepare an evaporated solution containing the alkalimetal taurinate by the ethylene oxide process; and an alkali metalbisulfite pipeline connected to the ion exchange unit and the reactionunit respectively, and configured to return the alkali metal bisulfiteto the reaction unit. Alkali metal bisulfite in the activating reagentand alkali metal bisulfite produced after activation can flow back tothe reaction unit via the alkali metal bisulfite pipeline to undergo anaddition reaction with ethylene oxide to produce alkali metalisethionate.

In a second aspect, the present disclosure proposes a method forpreparing taurine. According to embodiments of the present disclosure,the method includes: preparing an evaporated solution containing alkalimetal taurinate by an ethylene oxide process in a reaction unit;independently treating each of at least one ion exchange resin column inan ion exchange unit by a first activation manner or a second activationmanner; dispensing a part of the evaporated solution containing thealkali metal taurinate to the at least one ion exchange resin columntreated by the first activation manner to obtain alkali metal bisulfiteand taurine, and inputting the alkali metal bisulfite into the reactionunit; and dispensing the other part of the evaporated solutioncontaining the alkali metal taurinate to the at least one ion exchangeresin column treated by the second activation manner to obtain alkalimetal sulfate and taurine. The method according to the embodiments ofthe present disclosure uses the ethylene oxide process to preparetaurine, and uses two kinds of ion exchange resin column activationsystems to achieve the balance of alkali metal ions in the continuousmass production process of taurine, thereby avoiding the problem ofdifficult disposal of redundant alkali metal ions produced in the ionexchange columns activated with sulfurous acid (an alkali metalbisulfite solution in which sulfur dioxide is dissolved), and achievingthe balance of alkali metal ions in the continuous production process.

According to the embodiments of the present disclosure, the above methodfurther includes at least one of the following additional technicalfeatures.

According to the embodiments of the present disclosure, the firstactivation manner further includes: passing alkali metal bisulfitethrough the ion exchange resin column from bottom to top; dissolvingsulfur dioxide in an alkali metal bisulfite solution to obtain asulfurous acid solution; and passing the sulfurous acid solution throughthe ion exchange resin column from top to bottom to treat the ionexchange resin column by the first activation manner. According to theembodiments of the present disclosure, if the ion exchange resin columnstays in the sulfurous acid environment for a long time, its activationefficiency will be reduced. Dissolution of sulfur dioxide in an alkalimetal bisulfite solution can improve the activation efficiency of theion exchange resin column, and shorten the activation time, butintroduces redundant alkali metal ions which need to be furtherbalanced.

According to the embodiments of the present disclosure, the secondactivation manner further includes: passing an alkali metal sulfatesolution through the ion exchange resin column from bottom to top; andpassing a sulfuric acid solution having a concentration smaller than orequal to 25 wt % through the ion exchange resin column from top tobottom to treat the ion exchange resin column by the second activationmanner. According to the embodiments of the present disclosure,activation of the ion exchange resin column with sulfuric acid at aconcentration smaller than or equal to 25 wt % can have a goodactivation effect and an improved activation efficiency, and balance thealkali metal ions in the production process of taurine so as to finallyproduce alkali metal sulfate.

Upon extensive studies, the inventors have found that the activationefficiency and production efficiency can be improved by pre-treating theion exchange resin column with an alkali metal salt solution from bottomto top before activating the ion exchange resin column with an acidsolution. A density of the alkali metal salt solution is higher thanthat of water, and when flowing from bottom to top, the alkali metalsalt solution is hardly mixed with water thoroughly, which is beneficialfor the alkali metal salt solution to push out residual aqueous solutionin the resin. The solution that is pushed out can directly enter anoriginal evaporated solution system. The alkali metal salt solution maybe a received solution with a pH value greater than 5 that is obtainedfrom the previous acid activation and contain a small number of hydrogenions that can be transformed into alkali metal salt after entering theion exchange resin column, and the alkali metal salt solution can becompletely transformed into alkali metal salt, which increases theconcentration of the alkali metal salt, and improves the productionefficiency.

According to the embodiments of the present disclosure, the methodfurther includes: dispensing 60 wt % to 95 wt % of the evaporatedsolution containing the alkali metal taurinate to the at least one ionexchange resin column treated by the first activation manner, anddispensing 5 wt % to 40 wt % of the evaporated solution containing thealkali metal taurinate to the at least one ion exchange resin columntreated by the second activation manner. According to the embodiments ofthe present disclosure, 5 wt %, 10 wt %, 15 wt %, 20 wt %, 25 wt %, 30wt %, 35 wt % or 40 wt % of the evaporated solution is dispensed intothe at least one ion exchange resin column treated by the secondactivation manner, and 60 wt %, 65 wt %, 70 wt %, 75 wt %, 80 wt %, 85wt %, 90 wt % or 95 wt % of the evaporated solution is dispensed intothe at least one ion exchange resin column treated by the firstactivation manner. Upon extensive studies, the inventors have found thatin the production process of taurine with the system of the presentdisclosure, extra strong alkali is added in the ammonolysis reactionprocess to adjust a pH value of the reaction system, and a small part ofthe strong alkali for adjusting the pH value will consume some activegroups in the resin in the ion exchange process. If an ion exchangeresin column is activated with sulfurous acid, one metal ion isdisplaced with one sulfurous acid to form an alkali metal salt, and onealkali metal salt can correspondingly produce one taurine molecule.Thus, if an ion exchange resin column is activated with sulfurous acidthat is produced by dissolving sulfur dioxide with alkali metalbisulfite, excessive alkali metal bisulfite will be present in theproduction system, a part of the alkali metal bisulfite cannot berecycled and reused, and excessive alkali metal ions are present in theproduction system. In order to solve this problem, a redundant alkalimetal bisulfite solution needs to be disposed. However, the directsewage disposal is high in cost and low in efficiency; and if anevaporation and concentration process is adopted, sodium bisulfite,sodium sulfite, etc. are unstable, and a salt obtained has high impuritycontent and cannot be sold, causing the waste of materials. By extensivestudies and a large number of experimental designs, the inventors havefound that if the ion exchange resin column activated by the firstactivation manner and the ion exchange resin column activated by thesecond activation manner are used to produce taurine from an evaporatedsolution at the same time, during activation of an exchange resin columnwith sulfuric acid, a part of alkali metal ions can be transformed intoalkali metal sulfate that belongs to strong alkali salts, and the alkalimetal sulfate can be directly concentrated by evaporation to form a pureproduct that can be sold or used. The disposal method is simple andsaves cost and resources.

According to the embodiments of the present disclosure, a ratio of theevaporated solution dispensed to the at least one ion exchange resincolumn treated by the first activation manner to the evaporated solutiondispensed to the at least one ion exchange resin column treated by thesecond activation manner ranges from (3:2) to (19:1).

According to the embodiments of the present disclosure, the methodfurther includes, prior to activation: independently determining aconcentration of alkali metal ions in an input solution of each of theat least one ion exchange resin column and a concentration of alkalimetal ions in the ion exchange resin column to determine an activationmanner of the activation to be performed on the ion exchange resincolumn, wherein the input solution and the output solution containalkali metal taurinate ions.

According to the embodiments of the present disclosure, the methodfurther includes: changing, in response to the concentration of alkalimetal ions in the output solution of the ion exchange resin column thatis being treated by the first activation manner being greater than orequal to 60% of the concentration of alkali metal ions in the inputsolution of the ion exchange resin column, the activation manner of theion exchange resin column to the second activation manner, and changing,in response to the concentration of alkali metal ions in the outputsolution being smaller than or equal to 5% of the concentration ofalkali metal ions in the input solution, the activation manner of theion exchange resin column to the first activation manner. According tothe embodiments of the present disclosure, when the concentration ofalkali metal ions in the output solution is greater than or equal to 60%of the concentration of alkali metal ions in the input solution, itindicates that the ion exchange resin column is not in a good usecondition, excessive alkali metal ions are present in the ion exchangeresin column, ion exchange performed on alkali metal salt taurine isinefficient, the activation manner performed on the ion exchange resincolumn needs to be changed, and the ion exchange resin column needs tobe activated with sulfuric acid. When the concentration of alkali metalions in the output solution is smaller than or equal to 5% of theconcentration of alkali metal ions in the input solution, it indicatesthat the ion exchange resin column is in a recovered state and can befurther activated with sulfurous acid (an alkali metal bisulfitesolution in which sulfur dioxide is dissolved), and activation withsulfurous acid will have a higher efficiency, which is beneficial to theefficient preparation of taurine in the continuous production process.

According to the embodiments of the present disclosure, a concentrationof the alkali metal bisulfite ranges from 30 wt % to 40 wt %, preferably35 wt %. According to the embodiments of the present disclosure, theconcentration of the alkali metal bisulfite is 30 wt %, 31 wt %, 32 wt%, 33 wt %, 34 wt %, 35 wt %, 36 wt %, 37 wt %, 38 wt %, 39 wt %, or 40wt %.

According to the embodiments of the present disclosure, theconcentration of the alkali metal sulfate ranges from 2 wt % to 15 wt %,preferably from 5 wt % to 10 wt %. According to the embodiments of thepresent disclosure, the concentration of the alkali metal sulfate is 2wt %, 3 wt %, 4 wt %, 5 wt %, 6 wt %, 7 wt %, 8 wt %, 9 wt %, 10 wt %,11 wt %, 12 wt %, 13 wt %, 14 wt %, or 15 wt %.

BRIEF DESCRIPTION OF DRAWINGS

The above and/or additional aspects and advantages of the presentdisclosure will become apparent and readily understood from thefollowing description of the embodiments in conjunction with theaccompanying drawings, in which:

FIG. 1 is a schematic diagram of a system for preparing taurineaccording to embodiments of the present disclosure;

FIG. 2 is a flowchart of a method for preparing taurine according toembodiments of the present disclosure;

FIG. 3 is a flowchart of sulfuric acid activation according toembodiments of the present disclosure; and

FIG. 4 is a variation curve of sodium sulfate with temperature accordingto embodiments of the present disclosure.

DESCRIPTION OF EMBODIMENTS

The embodiments of the present disclosure will be described below indetail, and examples of the embodiments are shown in the drawings. Theembodiments described below with reference to the drawings areexemplary, and are intended to explain the present disclosure and shouldnot be construed as limiting the present disclosure.

Explanation of Terms

Unless otherwise specified, the terms “first”, “second”, “third”, etc.herein are used for convenience of description and distinguishing, donot imply or express a difference in order or importance therebetween,and do not indicate that the content defined by “first”, “second”,“third”, etc. is composed of only one component.

In the present disclosure, unless otherwise expressly specified andlimited, the terms “install”, “link”, “connect”, “fix”, etc. should beunderstood in a broad sense. For example, it may be a fixed connection,a detachable connection, or an integrated body; it may be a mechanicalconnection or an electrical connection; it may be a direct connection oran indirect connection through an intermediate; and it may be internalcommunication between two elements or interaction relationship betweenthe two elements. Those of ordinary skill in the art can understand thespecific meanings of the above terms in the present disclosure accordingto specific situations.

In the present disclosure, unless otherwise expressly specified andlimited, a first feature being “above” or “below” a second feature maymean that the first feature is in direct contact with the secondfeature, or the first feature is in indirect contact with the secondfeature through an intermediate. Moreover, the first feature being“above”, “over”, or “on” the second feature may mean that the firstfeature is directly or obliquely above the second feature, or simplymeans that the first feature has a higher level than the second feature.The first feature being “below”, “under” or “beneath” the second featuremay mean that the first feature is just or obliquely below the secondfeature, or simply means that the first feature has a lower level thanthe second feature.

It should be noted that “alkali metal salt”, “alkali metal”, etc. hereininclude “sodium salt, potassium salt and/or lithium salt”, “sodium,potassium and/or lithium”. For example, alkali metal bisulfite refers tosodium bisulfite, potassium bisulfite or lithium bisulfite.

It should be noted that the alkali metal salt herein is preferablysodium salt.

It should be noted that an original evaporated solution herein refers toan evaporated solution obtained by evaporation or flash evaporationafter an ammonolysis reaction. The evaporated solution has not beentreated with any diluent, and has not been reacted with any otherreagent (e.g., an acid solution).

It should be noted that the evaporated solution herein includes theoriginal evaporated solution and/or an evaporated solution that has beensubjected to treatment, and the treatment includes, but is not limitedto, dilution with water or other solutions, neutralization with an acidsolution (e.g., isethionic acid), etc.

It should be noted that a resin column, an ion exchange resin column, anion exchange column, etc. herein all refer to a weakly acidic cationresin column having an acidity that is slightly higher than that oftaurine.

In a first aspect, the present disclosure proposes a system forpreparing taurine. Referring to FIG. 1 , according to the embodiments ofthe present disclosure, the system includes: a solution storage unit 100configured to store a solution containing alkali metal taurinate that isprepared by an ethylene oxide process; an ion exchange unit 200connected to the solution storage unit 100 and including at least oneion exchange resin column; and a dispensing unit 300 connected to thesolution storage unit 100 and the ion exchange unit 200 respectively,and configured to adjust an amount of the solution conveyed from thesolution storage unit 100 to each of the at least one ion exchange resincolumn in the ion exchange unit 200. Each ion exchange resin column isactivated independently by a first activation manner or a secondactivation manner, the first activation manner uses sulfurous acid foractivation to obtain alkali metal bisulfite and taurine, and the secondactivation manner uses sulfuric acid for activation to obtain alkalimetal sulfate and taurine. According to the embodiments of the presentdisclosure, the system has high efficiency, energy saving, and resourcesaving advantages.

According to the embodiments of the present disclosure, the systemfurther includes: a reaction unit 400 connected to the solution storageunit 100 and configured to prepare an evaporated solution containingalkali metal taurinate by the ethylene oxide process; and an alkalimetal bisulfite pipeline 500 connected to the ion exchange unit 200 andthe reaction unit 400 respectively, and configured to return the alkalimetal bisulfite to the reaction unit 400. Alkali metal bisulfite in anactivating reagent and alkali metal bisulfite produced after activationcan flow back to the reaction unit 400 via the alkali metal bisulfitepipeline 500 and undergo an addition reaction with ethylene oxide toproduce alkali metal isethionate.

According to the embodiments of the present disclosure, the number ofthe ion exchange resin columns in the ion exchange unit is not limited,which may be one, two or more. At the same time, a quantity ratio of ionexchange resin columns treated by the first activation manner to ionexchange resin columns treated by the second activation manner may be1:1, 2:1, or 3:1, preferably 1:1 or 2:1.

In a second aspect, the present disclosure proposes a method forpreparing taurine. According to embodiments of the present disclosure,the method includes: preparing an evaporated solution containing alkalimetal taurinate by an ethylene oxide process in a reaction unit;independently treating each of at least one ion exchange resin column inan ion exchange unit by a first activation manner or a second activationmanner; dispensing a part of the evaporated solution containing thealkali metal taurinate to the at least one ion exchange resin columntreated by the first activation manner to obtain alkali metal bisulfiteand taurine, and inputting the alkali metal bisulfite into the reactionunit; and dispensing the other part of the evaporated solutioncontaining the alkali metal taurinate to the at least one ion exchangeresin column treated by the second activation manner to obtain alkalimetal sulfate and taurine.

Referring to FIG. 2 , according to a specific embodiment of the presentdisclosure, the method includes specific steps as follows.

1. Ethylene oxide reacts with alkali metal bisulfite to prepare alkalimetal isethionate which reacts with ammonia under alkaline conditions toprepare alkali metal taurinate, and the solution obtained afterammonolysis reaction is subjected to flash evaporation and/orevaporation to remove redundant ammonia, so as to obtain the evaporatedsolution.

2. The evaporated solution is dispensed to the resin columns in the ionexchange unit according to a proportion, that is, 60 wt % to 95 wt % ofthe evaporated solution enters the resin columns treated by the firstactivation manner, and 5 wt % to 40 wt % of the evaporated solutionenters the resin columns treated in the second activation solution.

3. Before the evaporated solution is subjected to ion exchange, the ionexchange resin columns are subjected to water washing, acid washing,alkali washing, activation, and water washing again. The water washingis performed to remove common impurities from an ion resin before theion resin is loaded into the column, and requires that the resin iswater-washed until the solution obtained from the water washing becomescolorless and no bubble is produced. The acid washing and alkali washingare performed to remove residual small molecule impurities in the resin.In the acid washing process, generally strong acid with a hydrogen ion[H]⁺ concentration of 1 mol/L is used, and the volume of the strong acidis 2 to 3 times that of the resin. After the acid washing, the resinneeds to be subjected to water washing until a pH value is 2 to 4 so asto remove an acid solution from the resin, and then the resin issubjected to alkali washing. In the alkali washing process, generallystrong alkali with a hydroxide ion [OH]⁻ concentration of 1 mol/L isused, and the volume of the strong alkali is 2 to 3 times that of theresin. After the alkali washing, the resin needs to be subjected towater washing again until a final pH value is 9 to 10. After beingcleaned, the resin is activated with a strongly acidic solution with ahydrogen ion [H]⁺ concentration of 1 mol/L and a volume of 2 to 4 timesthat of the resin. After being activated, the resin is subjected towater washing again until a pH value is less than 9. The solutionobtained from the last water washing after the activation can bedirectly reused to prepare acid for the next activation of the resin.

4. The evaporated solution is inputted into the ion exchange columntreated by the first activation manner from top to bottom. If a pH valueof an output solution of the resin is less than 3, the output solutionis used to dilute and neutralize an original evaporated solution; if thepH value of the output solution is 3 to 8, the output solutioncontaining taurine is collected; and if the pH value of the outputsolution is greater than 8, the evaporated solution is no longerinputted. The concentration of alkali metal ions in the output solutionobtained at this step is detected.

5. Purified water is flowed through the ion exchange column from top tobottom to wash the resin that has been used, and an output solution ofthe resin produced in the washing process is used to dilute theevaporated solution, until no taurine is detected in the outputsolution. At this time, a pH value of the output solution is 9.5 to10.5. This step can reduce the usage amount of water and save water.

6. After the resin column treated by the first activation manner iswashed, a sodium bisulfite solution at a low concentration is inputtedinto the ion exchange column from bottom to top to push out residualwater in the resin column. A part of the residual water that is pushedout is used to dilute the original evaporated solution so as to avoidthe waste of water, and the other part of the residual water isdischarged for external collection and disposal to avoid the mixing ofsodium bisulfite into the evaporated solution.

7. After water is removed from the ion exchange column treated by thefirst activation manner, the ion exchange column is activated with amixture of sulfur dioxide, sodium bisulfite, and sulfurous acid from topto bottom, the addition of the activating reagent is stopped in responseto the pH value of the output solution being 3 to 4, and the outputsolution is stored and used to prepare sodium bisulfite.

8. After the resin column is activated by the first activation manner,purified water is inputted into the ion exchange column from top tobottom until no acid radical anion is detected in the output solution ofthe resin. At this time, a pH value of the output solution is about 4,the purified water is no longer inputted, and the output solution isused to prepare sodium bisulfite. According to the embodiments of thepresent disclosure, this step can reduce the usage amount of water, savewater, and control the production cost.

9. An appropriate volume of a solution containing alkali metal sulfiteis used to push out water in apertures of the resin in the ion exchangecolumn activated by the first activation manner from bottom to top. Theoutput solution obtained at this step is treated by two steps: theoutput solution with a pH value greater than 3 is returned to theevaporated solution, and the output solution with a pH value less than 3is directly collected as a finished product solution. In response to thevolume of the output solution being the same as a volume of the inputsolution entering the resin, the inputting of the solution containingalkali metal sulfite is stopped, and a diluted evaporated solution isinputted. According to the embodiments of the present disclosure, theion exchange resin column is pre-treated with taurine, which can providean alkali metal bisulfite-containing environment for the resin column inadvance, reduce damage of a strongly alkaline evaporated solution to theresin column, use active groups in the resin column to the largestextent, improve the activation efficiency, protect the resin column, andprolong the service life of the resin column.

10. The steps of washing the resin, activating the resin, washing theresin, and inputting the evaporated solution are cycled to achieveefficient continuous production of taurine. However, when an ionexchange resin column is activated with a sulfurous acid system, thecycle number is increased due to incomplete activation of the resin, sothat the system is collapsed, and cycling cannot be continued.Therefore, when an ion exchange column is being treated by the firstactivation manner, the first activation manner of the ion exchange resincolumn is adjusted to the second activation manner, namely the sulfuricacid activation manner, in response to the concentration of alkali metalions in the output solution being greater than 60% of the concentrationof alkali metal ions in the evaporated solution inputted. In the cyclingprocess, in response to the concentration of alkali metal ions in theoutput solution being less than 5% of the concentration of alkali metalions in the input solution, the activation manner is adjusted to thesulfurous acid activation manner.

11. When treated by the second activation manner, an ion exchange resinis subjected to the same steps as those performed by the firstactivation manner except the step of activation of the ion exchangeresin column and the treatment prior to the activation.

12. When the second activation manner is adopted to treat an ionexchange resin, the treatment (an alkali metal salt is used to push outwater) prior to the activation includes: pushing out residual water inthe resin from bottom to top with an alkali metal salt after the resincolumn is subjected to water washing. A part of a solution that ispushed out and contains no sulfate ions is inputted into the originalevaporated solution to dilute the evaporated solution, and the otherpart of the solution that is pushed out and contains sulfate ions isdirectly inputted into a diluted acid storage tank and used to preparean activating reagent.

13. The second activation manner is performed with diluted sulfuric acidfrom top to bottom. The output solution with a pH value greater than 5is inputted into a sodium sulfate storage tank, the output solution witha pH value less than 5 is inputted into the diluted acid storage tank,and the inputting of the dilute sulfuric acid is stopped in response thepH value of the output solution being less than 3. The activationprocess is shown in FIG. 3 . In order to improve the activationefficiency, the concentration of the diluted sulfuric acid is less than23% wt. By a large number of experiments, the inventors have found thatafter the evaporated solution is passed through the resin column, theresin column is subjected to water washing, and after the water washing,residual water in the resin column is pushed out with the outputsolution with a pH value from 5 to 5.5, and the output solution with apH value less than 5 is used as a next batch activating reagent whichcontains a part of acid and a part of sodium sulfate. Increase of theconcentration of sulfuric acid can reduce the use volume of sulfuricacid for activation to a small extent, but complete acid activation haslittle to do with the concentration of acid, and affects the subsequentstep of purification of sodium sulfate. The saturated mass fraction ofsodium sulfate is 31.6%, and at this time, a maximum concentration ofthe corresponding sulfuric acid is not greater than 23%. If theconcentration of sulfuric acid is too high, sodium sulfate will beprecipitated to cause solid blockage; a low concentration of thesulfuric acid has minimal damage to the resin, but a too lowconcentration in the production process can result in difficulties insubsequent purification of sodium sulfate, high usage amount of water,and thus a high cost.

The above order is not the specific order of the method for preparingtaurine, and is only set herein for the convenience of understanding thepresent disclosure. In the actual production process, the number of ionexchange resin columns in the ion exchange unit and the activationmanners can be adjusted according to the actual production capacity.That is, the first activation manner and the second activation mannercan be performed alternately on the same ion exchange resin column, orperformed on different ion exchange resin columns at the same time, orperformed alternately on different ion exchange resin columns.

The present disclosure will be described below with reference tospecific examples. It should be noted that these examples are only forthe illustrative purpose, and are not construed as limiting the presentdisclosure.

Example 1

1. Resin pretreatment: 1 L of resin was loaded into a chromatographiccolumn and pressed tightly, 3 to 5 cm of water was kept on the top ofthe resin, the resin was treated with a 4% sulfuric acid solution with avolume that is 3 times the volume of the resin at a flow rate of 2 to 4times the volume of the resin per hour; after the treatment wascompleted, the resin was washed with tap water until a pH value of anoutput solution was greater than 4, then the resin was transformed witha 4% NaOH solution with a volume of 1.5-2 times the volume of resin (BV)at a flow rate of 2 to 4 times the volume of the resin per hour; afterthe transformation was completed, the resin was washed with tap wateruntil a pH value of an output solution was less than 9. The resin wastreated with a 4% sulfuric acid solution with a volume that is 3 timesthe volume of the resin at a flow rate of 2.5-5 BV/h, and after thetreatment was completed, the resin was washed with tap water until a pHvalue of an output solution was greater than 4, so as to complete theactivation of the resin for later use.

2. Flowing of evaporated solution sample through column: an originalevaporated solution was diluted until the content of alkali metaltaurinate was about 20 wt %, the diluted evaporated solution flowedthrough the column in a forward direction at a certain flow rate foradsorption, an end point was determined according to the requirements ofdifferent time periods, and various indicators were measured. After theflowing of the evaporated solution sample was completed, the ionexchange column was washed with water until a pH value of an outputsolution was 8 to 9, indicating that the elution was completed.

3. Regeneration of resin: the resin was treated by the first activationmanner or the second activation manner.

4. Steps 2 and 3 were cycled in the same ion exchange column, and ineach cycle, 100 L of the evaporated solution flowed through the column,and the cycle was repeated 10 times.

Allocated volume corresponding to activation at steps 3 and 4 are shownin Table 1.

TABLE 1 Allocated volume of taurine flowing through column for differentactivation manners 1 2 3 4 5 6 7 8 9 10 First activation 100 L 100 L 95L 95 L 80 L 80 L 60 L 60 L 55 L 55 L manner Second activation 0 0  5 L 5 L 20 L 20 L 40 L 40 L 45 L 45 L manner

Results are shown in Table 2.

TABLE 2 Total molar quantity of produced taurine and total molarquantity of produced sodium bisulfite in Example 1 Molar quantity oftaurine/mol First Second Total molar Molar quantity of activationactivation quantity of newly produced manner manner taurine/mol sodiumbisulfite/mol 1 15.2 0 15.2 16.9 2 15.3 0 15.3 16.8 3 14.6 0.79 15.1915.7 4 14.4 0.78 15.18 15.6 5 12.3 3.0 15.1 14.6 6 12.1 3.1 15.2 14.5 79.1 6.2 15.3 12.1 8 9.2 6.21 15.33 12.7 9 8.3 7.1 15.4 9.8 10 8.2 7.515.1 10.0

It can be seen from Table 2 that, flowing and transformation of 100 L ofevaporated solution at a (alkali metal taurinate) concentration of 20 wt% through one ion resin column produce taurine, 10 samples of 100 L ofevaporation solutions were used for 10 cycles (100 L each cycle), andthe activation manner performed on the resin is changed every twocycles. As shown in Table 1, for the first and second cycles, 100 L ofevaporated solution flowed through the column and the adopted activationmanner was the first activation manner and for the third to tenthcycles, activation by the first activation manner was used for a flowingvolume of 95 L, 80 L, 60 L, and 55 L of evaporated solution, andactivation by the second activation manner was used for the remainingflowing volume of 5 L, 20 L, 40 L, and 45 L of evaporated solution. Itcan be seen from Table 2 that when 100 L of evaporated solution flowsthrough the column and the first activation manner was adopted, themolar quantity of produced sodium bisulfite is greater than the molarquantity of sodium taurinate entering the system. In the presentdisclosure, in the ethylene oxide process for preparing taurine, 1 molof alkali metal sulfite correspondingly produces 1 mol of taurine. Asfor 100 L of evaporated solution, when activation by the firstactivation manner was used for a flowing volume of 95 L of evaporatedsolution, and activation by the second activation manner was used for aflowing volume of 5 L of evaporated solution, the content of the newlyproduced sodium bisulfite is still higher than that of the producedtaurine (this is because in the cycling system, sodium bisulfite is usedto push out water, a small amount of sodium is discharged and disposedas sewage, and the balance of sodium in the system can be basicallyachieved). As for 100 L of evaporated solution, when the firstactivation manner was used for a flowing volume of 80 L, 60 L or 55 L ofevaporated solution, and the second activation manner was used for aflowing volume of 20 L, 40 L or 45 L of evaporated solution, the molarquantity of the newly produced sodium bisulfite is less than the totalmolar quantity of taurine, no redundant sodium bisulfite needs to bedisposed in the system, and extra sodium bisulfite is needed tosupplemented to produce taurine. However, supplement of excessive sodiumbisulfite to the system is not beneficial to improvement of the overallproduction efficiency. Through comprehensive consideration, a totalvolume of the evaporated solution for the treatment with the firstactivation manner accounts for 60% to 95%, and a total volume of theevaporated solution for the treatment with the second activation manneraccounts for 5% to 40%.

Example 2 Comparative Example 1

1. Resin pretreatment: 6 L of resin was loaded into a chromatographiccolumn and pressed tightly, 3 to 5 cm of water was kept on the top ofthe resin, the resin was treated with a 4% sulfuric acid solution with avolume that is 3 times the volume of the resin at a flow rate of 2 to 4times the volume of the resin per hour; after the treatment wascompleted, the resin was washed with tap water until a pH value of anoutput solution was greater than 4, then the resin was transformed witha 4% NaOH solution with a volume of 1.5 to 2 BV at a flow rate of 2 to 4times the volume of the resin per hour, and after the transformation wascompleted, the resin was washed with tap water until a pH value of anoutput solution was less than 9. The resin was treated with a 4%sulfuric acid solution with a volume that is 3 times the volume of theresin at a flow rate of 2.5 to 5 BV/h, and after the treatment wascompleted, the resin was washed with tap water until a pH value of anoutput solution was greater than 4, so as to complete the activation ofthe resin for later use.

2. Loading of resin into column: 6 L of activated resin was loaded intotwo chromatographic columns equally and pressed tightly, 3-5 cm of waterwas kept on the top of each resin, and the resin columns were numberedas A1 and B1, respectively.

3. Flowing of evaporated solution sample through column: an originalevaporated solution was diluted until the concentration of alkali metaltaurinate was about 20 wt %, the diluted evaporated solution flowedthrough the column in a forward direction at a certain flow rate foradsorption, an end point was determined according to the requirements ofdifferent time periods, and various indicators were measured. After theflowing of the evaporated solution sample was completed, the resincolumn was washed with water until a pH value of an output solution was8 to 9, indicating that elution was completed.

4. Regeneration of resin: the resin column A1 was treated by the firstactivation manner, and the resin column B1 was treated by the secondactivation manner.

Steps 3 and 4 were cycled, 100 L of evaporated solution flowed throughthe ion resin column A1, a total quantity of the finally obtainedtaurine was detected, and a content of the newly produced sodiumbisulfite was also detected.

Comparative Example 2

3. Flowing of evaporated solution sample through columns: an originalevaporated solution was diluted until the concentration of alkali metaltaurinate was about 20 wt %, the diluted evaporated solution flowedthrough the column in a forward direction at a certain flow rate foradsorption, an end point was determined according to the requirements ofdifferent time periods, and various indicators were measured. After theflowing of the evaporated solution was completed, the resin column waswashed with water until a pH value of an output solution was 8 to 9,indicating elution was completed.

4. Regeneration of resin: the resin column A1 was treated by the firstactivation manner, and the resin column B1 was treated by the secondactivation manner.

Steps 3 and 4 were cycled, 95 L of evaporated solution flowed throughthe ion resin column A1, 5 L of evaporated solution flowed through theion resin column B2, the total quantity of the finally obtained taurinewas detected, and the content of the newly produced sodium bisulfite wasalso detected.

Comparative Example 3

3. Flowing of evaporated solution sample through column: an originalevaporated solution was diluted until the concentration of alkali metaltaurinate was about 20 wt %, the diluted evaporated solution flowedthrough the column in a forward direction at a certain flow rate foradsorption, an end point was determined according to the requirements ofdifferent time periods, and various indicators were measured. After theflowing of the evaporated solution was completed, the resin column waswashed with water until a pH value of an output solution was 8 to 9,indicating that elution was completed.

4. Regeneration of resin: the resin column A1 was treated by the firstactivation manner, and the resin column B1 was treated by the secondactivation manner.

Steps 3 and 4 were cycled, 80 L of evaporated solution flowed throughthe ion resin column A1, 20 L of evaporated solution flowed through theion resin column B2, the total quantity of the finally obtained taurinewas detected, and the content of the newly produced sodium bisulfite wasalso detected.

Comparative Example 4

3. Flowing of evaporated solution sample through column: an originalevaporated solution was diluted until the concentration of alkali metaltaurinate was about 20 wt %, the diluted evaporated solution flowedthrough the column in a forward direction at a certain flow rate foradsorption, an end point was determined according to the requirements ofdifferent time periods, and various indicators were measured. After theflowing of the evaporated solution was completed, the resin column waswashed with water until a pH value of an output solution was 8 to 9,indicating that elution was completed.

4. Regeneration of resin: the resin column A1 was treated by the firstactivation manner, and the resin column B1 was treated by the secondactivation manner.

Steps 3 and 4 were cycled, 60 L of evaporated solution flowed throughthe ion resin column A1, 40 L of evaporated solution flowed through theion resin column B2, the total quantity of the finally obtained taurinewas detected, and the content of the newly produced sodium bisulfite wasalso detected.

Comparative Example 5

3. Flowing of evaporated solution sample through column: an originalevaporated solution was diluted until the concentration of alkali metaltaurinate was about 20 wt %, the diluted evaporated solution flowedthrough the column in a forward direction at a certain flow rate foradsorption, an end point was determined according to the requirements ofdifferent time periods, and various indicators were measured. After theflowing of the evaporated solution was completed, the resin column waswashed with water until a pH value of an output solution was 8 to 9,indicating that elution was completed.

4. Regeneration of resin: the resin column A1 was treated by the firstactivation manner, and the resin column B1 was treated by the secondactivation manner.

Steps 3 and 4 were cycled, 55 L of evaporated solution flowed throughthe ion resin column A1, 45 L of evaporated solution flowed through theion resin column B2, the total quantity of the finally obtained taurinewas detected, and the content of the newly produced sodium bisulfite wasalso detected.

Results are shown in the following table.

TABLE 3 Total molar quantity of produced taurine and total molarquantity of produced sodium bisulfite in Comparative Examples 1 to 5 ofExample 2 Molar quantity of Total molar Molar quantity of taurine/molquantity of newly produced A1 B1 taurine/mol sodium bisulfite/molComparative 15.2 0 15.2 16.8 Example 1 Comparative 14.4 0.78 15.18 15.7Example 2 Comparative 12.1 3.1 15.2 14.5 Example 3 Comparative 9.1 6.215.3 12.1 Example 4 Comparative 8.3 7.1 15.4 9.8 Example 5

It can be seen from Table 3 that flowing and transformation of 100 L of20 wt % evaporated solution through the ion resin columns A1 and B1obtain taurine. In Comparative Example 1, the evaporated solution allflowed through the column A1 (the resin was activated by the firstactivation manner), and the molar quantity of finally produced sodiumbisulfite is greater than the molar quantity of sodium taurinateentering the system. In the present disclosure, in the ethylene oxideprocess for preparing taurine, 1 mol of alkali metal sulfitecorrespondingly produces 1 mol of taurine. In Comparative Example 2, 95L of evaporated solution flowed through the column A1, 5 L of evaporatedsolution flowed through the column B1 (column B1 was treated by thesecond activation manner), and the content of newly produced sodiumbisulfite was still higher than that of produced taurine (that isbecause in the cycling system, a small amount of sodium in a portion ofsodium bisulfite used to push out water was discharged and disposed assewage, and the balance of sodium in the system can be basicallyachieved). In Comparative Examples 3, 4 and 5, 80 L, 60 L, and 55 L ofevaporated solutions flowed through the column A1, 20 L, 40 L, and 45 Lof evaporated solutions flowed through the column B1, the molar quantityof newly produced sodium bisulfite is less than the total molar quantityof taurine, no redundant sodium bisulfite needs to be disposed in thesystem, and extra sodium bisulfite is needed to supplemented to producetaurine. However, supplement of excessive sodium bisulfite to the systemis not beneficial to improvement of the overall production efficiency.Through comprehensive consideration, a total volume of the evaporatedsolution entering the ion exchange resin column that is treated by thefirst activation manner accounts for 60% to 95%, and a total volume ofthe evaporated solution entering the ion exchange resin column that istreated by the second activation manner accounts for 5% to 40%.

Example 3

1. Resin pretreatment: 6 L of resin was loaded into a chromatographiccolumn and pressed tightly, 3 to 5 cm of water was kept on the top ofthe resin, the resin was treated with a 4% sulfuric acid solution with avolume that is 3 times the volume of the resin at a flow rate of 2 to 4times the volume of the resin per hour; after the treatment wascompleted, the resin was washed with tap water until a pH value of anoutput solution was greater than 4, then the resin was transformed witha 4% NaOH solution with a volume of 1.5-2 BV at a flow rate of 2-4 timesthe volume of the resin per hour, and after the transformation wascompleted, the resin was washed with tap water until a pH value of anoutput solution was less than 9. The resin was treated with a 4%sulfuric acid solution with a volume that is 3 times the volume of theresin at a flow rate of 2.5-5 BV/h, and after the treatment wascompleted, the resin was washed with tap water until a pH value of anoutput solution was greater than 4, so as to complete the activation ofthe resin for later use.

2. Loading of resin into column: 6 L of activated resin was loaded intoeach of six chromatographic columns in an equal volume and pressedtightly, 3 to 5 cm of water was kept on the top of the resin, and theresin columns were numbered as A, B, C, D, E, and F, respectively.

Comparative Example 6

3. Flowing of evaporated solution sample through column: 6 samples of1.5 L of 20 wt % evaporated solution (1.5 L each portion) were dilutedto volume according to a certain ratio and flowed through the columns ina forward direction at a certain flow rate for absorption, an end pointwas determined according to the requirements of different time periods,and various indicators were measured. After the flowing of theevaporated solution was completed, the resin column was washed withwater until a pH value of an output solution was 8 to 9, indicatingelution was completed.

4. Regeneration of resin: the resin in columns A, B, and C was activatedwith sulfurous acid, and the resin in columns D, E, and F was activatedwith sulfuric acid.

Steps 3 and 4 were cycled 40 times.

Comparative Example 7

3. Flowing of evaporated solution sample through column: 6 samples of1.5 L of 20 wt % evaporated solution (1.5 L each portion) were dilutedto volume according to a certain ratio and flowed through the columns ina forward direction at a certain flow rate for absorption, an end pointwas determined according to the requirements of different time periods,and various indicators were measured. After the flowing of theevaporated solution was completed, the resin column was washed withwater until a pH value of an output solution was 8 to 9, indicatingelution was completed.

4. Regeneration of resin: the resin in columns D, E, and F was activatedwith the sulfurous acid activation system, and the resin in columns A,B, and C was activated with sulfuric acid.

Steps 3 and 4 were cycled 40 times.

Comparative Example 8

3. Flowing of evaporated solution sample through column: 6 samples of1.5 L of 20 wt % evaporated solution (1.5 L each portion) were dilutedto volume according to a certain ratio and flowed through the columns ina forward direction at a certain flow rate for absorption, an end pointwas determined according to the requirements of different time periods,and various indicators were measured. After the flowing of theevaporated solution was completed, the resin column was washed withwater until a pH value of an output solution was 8 to 9, indicatingelution was completed.

4. Regeneration of resin: the resin in columns A, B, C and D wasactivated with the sulfurous acid activation system, and the resin incolumns E and F was activated with sulfuric acid.

Steps 3 and 4 were cycled 40 times.

Comparative Example 9

3. Flowing of evaporated solution sample through column: 6 samples of1.5 L of 20 wt % evaporated solution (1.5 L each portion) were dilutedto volume according to a certain ratio and flowed through the columns ina forward direction at a certain flow rate for absorption, an end pointwas determined according to the requirements of different time periods,and various indicators were measured. After the flowing of theevaporated solution was completed, the resin column was washed withwater until a pH value of an output solution was 8 to 9, indicatingelution was completed.

4. Regeneration of resin: the resin in columns C, D, E and F wasactivated by the first activation manner, and the resin in columns A andB was activated by the second activation manner.

Steps 3 and 4 were cycled 40 times.

Comparative Example 10

3. Flowing of evaporated solution sample through column: 6 samples of1.5 L of 20 wt % evaporated solution (1.5 L each portion) were dilutedto volume according to a certain ratio and flowed through the columns ina forward direction at a certain flow rate for absorption, an end pointwas determined according to the requirements of different time periods,and various indicators were measured. After the flowing of theevaporated solution was completed, the resin column was washed withwater until a pH value of an output solution was 8 to 9, indicatingelution was completed.

4. Regeneration of resin: the resin in columns A, B, E and F wasactivated by the first activation manner, and the resin in columns C andD was activated by the second activation manner.

Steps 3 and 4 were cycled 40 times.

Results are shown in Table 4 and Table 5.

TABLE 4 Variation of transformed quantity of alkali metal salt in theevaporated solutions in Comparative Examples 6 and 7 Cycle number10^(th) cycle 20^(th) cycle 30^(th) cycle 40^(th) cycle Comparative A95.6% 95.2% 92.7% 90.4% Example 6 B 96.7% 95.2% 93.4% 90.2% C 95.8%94.9% 93.1% 90.0% D 95.3% 95.1% 95.1%  95% E 96.9% 94.9% 95.6%  95% F95.8% 96.1% 96.3%  95% Comparative A 94.7% 95.4% 96.3% 95.3% Example 7 B95.9% 96.7% 94.9% 95.6% C 96.3% 96.3% 94.5% 96.1% D 95.9% 93.8% 92.9%90.5% E 94.8% 94.6% 91.8% 89.5% F 93.9% 93.2% 92.9% 88.7%

It can be seen from Table 4 that in Comparative Example 6, the resin incolumns A, B, and C was activated by the first activation manner, andafter the long-term activation, the activation efficiency of the resinwas reduced, and the transformation efficiency is reduced as the cyclenumber is increased; the resin in columns D, E, and F was activated bythe second activation manner, and after the long-term activation, theactivation efficiency of the resin did not change, and thetransformation efficiency of the evaporated solution was stable. InComparative Example 7, the resin columns A, B, and C was activated bythe second activation manner instead of the first activation manneradopted in Comparative Example 6, the results show that thetransformation efficiency of the resin columns A, B, and C wasrecovered; the resin in columns D, E, and F was treated by the firstactivation manner, and as the number of activations is increased, theactivation efficiency of the resin was reduced and the transformationefficiency of the resin was reduced.

TABLE 5 Variation of transformed quantity of evaporated solution inComparative Examples 8, 9 and 10 Cycle number 10^(th) cycle 20^(th)cycle 30^(th) cycle 40^(th) cycle Comparative A 95.6% 94.7% 93.5% 91.5%Example 8 B 96.7% 94.6% 93.6% 92.5% C 94.8% 94.9% 94.1% 92.8% D 95.8%94.5% 93.3% 93.1% E 95.6% 94.8% 95.5% 94.9% F 96.7% 95.3% 97.6% 97.1%Comparative A 93.5% 94.8% 95.6% 96.1% Example 9 B 93.8% 94.6% 94.9%96.7% C 92.7% 91.8% 89.9% 88.5% D 93.4% 92.1% 89.5% 87.3% E 96.12% 94.8%93.6% 92.7% F 93.8% 94.6% 93.9% 92.7% Comparative A 95.8% 94.8% 93.9%92.9% Example 10 B 96.4% 94.9% 93.8% 93.1% C 93.5% 94.8% 95.6% 96.1% D93.8% 94.6% 94.9% 96.7% E 92.1% 92.0% 88.9% 88.6% F 93.1% 91.8% 89.7%87.5%

It can be seen from the results shown in Table 5 that in ComparativeExample 8, the resin columns A, B, C, and D were treated by the firstactivation manner, and the activation efficiency was reduced as thecycle number was increased. In Comparative Example 9, the resin columnsA and B were treated by the second activation manner instead, the resincolumns C and D were still treated by the first activation manner, andthe activation efficiency of the resin columns C and D was furtherreduced. In Comparative Example 10, the resin columns C and D weretreated by the second activation manner instead, and the transformationcapacity of the resin was recovered to a high level.

Therefore, it can be seen from Comparative Examples 6 to 10 that for anion exchange resin column treated by the first activation manner, if theresin is activated with sulfurous acid and sodium bisulfite for a longtime, the transformation efficiency of the resin is reduced as the cyclenumber is increased, and after the resin is changed to be treated by thesecond activation manner, the transformation efficiency of the resin isrecovered. It can be seen from the examples that for a resin columntreated by the first activation manner, when the detected concentrationof alkali metal in an output solution of the resin is about 60% of theconcentration of alkali metal in the evaporated solution entering theresin column, it indicates that the activation manner needs to bechanged to the second activation manner. For a resin column treated bythe second activation manner, when the detected concentration of alkalimetal in an output solution of the resin is about 5% of theconcentration of alkali metal in the evaporated solution entering theresin column, it is determined that the resin column is completelyactivated, and can be treated by the first activation manner or thesecond activation manner.

Example 4

The resin column C or D of Comparative Example 10 was selected toundergo the following experiment, and the resin column was treated bythe second activation manner.

3. Flowing of evaporated solution sample through column: an evaporatedsolution was diluted to a volume according to a certain ratio, a certainvolume of pre-treated resin was transferred into a chromatographiccolumn, the diluted evaporated solution flowed through the resin columnin a forward direction at a certain flow rate for adsorption, an endpoint was determined according to the requirements of different timeperiods, and various indicators were measured. After the flowing of theevaporated solution was completed, the resin column was washed withwater until a pH value of an output solution was 8 to 9, indicating thatelution was completed.

4. Regeneration of resin: a sulfuric acid solution flowed through thecolumn in a forward direction at a certain flow rate for desorption, itwas determined that the resin was completely activated in response todetecting no sodium ion in an eluent, and then the resin column waswashed with water until a pH value of an output solution was greaterthan 4.

Experimental steps 3 and 4 were repeated, the conditions of step 3 werekept unchanged, and the metal ion content in the activating reagentcontent of step 4 was changed. The conditions are shown in Table 6.

TABLE 6 Activation time under mixed eluents with the same sulfuric acidcontent (15 wt %) and different alkali metal ion contents Batch numberIngredient 1 2 3 4 5 6 7 Sulfuric acid 15 wt % 15 wt % 15 wt % 15 wt %15 wt % 15 wt % 15 wt % Sodium ion salt  0  2 wt %  5 wt %  8 wt % 10 wt% 12 wt % 15 wt % Activation time/min 60 55 46 43 45 47 46 Batch numberIngredient 8 9 10 11 12 13 14 Sulfuric acid 15 wt % 15 wt % 15 wt % 15wt % 15 wt % 15 wt % 15 wt % Magnesium ion salt  0  2 wt %  5 wt %  8 wt% 10 wt % 12 wt % 15 wt % Activation time 61 57 49 48 48 50 51 Batchnumber Ingredient 15 16 17 18 19 20 21 Sulfuric acid 15 wt % 15 wt % 15wt % 15 wt % 15 wt % 15 wt % 15 wt % Potassium ion salt  0  2 wt %  5 wt%  8 wt % 10 wt % 12 wt % 15 wt % Activation time 60 56 47 45 45 47 48

The results in Table 6 show that under the conditions of the same flowrate and the same sulfuric acid content, when the sodium salt content iszero, the resin needs to be activated for 60 min. The activation time ofthe resin is gradually reduced as the sodium ion salt content isincreased. However, when the sodium ion salt content is increased to 10wt % or more, the activation time does not change significantly, and inthis case, a sodium salt is precipitated in the resin to block thecolumn. Therefore, the optimal sodium ion salt content is between 5 wt %and 10 wt %. An enhancement effect of potassium ions is relativelyconsistent with that of sodium ions. An enhancement effect of amagnesium ion salt is relatively poor compared with that of a sodium ionsalt, but still has an enhancement effect. Sodium ions and potassiumions are all metal ions of group I and have similar structures, and themain ions to be exchanged in the ion resin system are sodium ions, sothe sodium salt and the potassium salt show a strong enhancement effect,and increase of the metal ion salts in the activating reagent canimprove the activation efficiency and shorten the activation time. Ifthe same type of metal ion salt is increased for production, theconcentration of the metal ion salt can be greatly increased, theevaporation cost is reduced, the subsequent recycling and reusing of themetal ion salt is enhanced, and the production cost is greatly saved.

Example 5

A variation curve of the solubility of sodium sulfate is as follows:

TABLE 7 Variation of solubility of sodium sulfate with temperatureTemperature/° C. 0 10 20 30 50 60 70 80 90 100 Solubility 4.9 9.1 19.540.8 46.2 45.3 44.3 43.7 42.7 42.5 Saturated mass 4.7% 8.3% 16.3% 29%31.6% 31.2% 30.7% 30% 29.9% 29.8% fraction g/g

It can be seen from FIG. 4 that when the temperature is below 50° C.,the solubility of sodium sulfate increases as the temperature increases,and when the temperature is above 50° C., the solubility of sodiumsulfate slowly decreases as the temperature increases. It can be seenthat when the temperature of the production system is kept at about 50°C., the acid concentration can be increased to the largest extent, andthe content of sodium sulfate obtained at this temperature is thehighest, which is beneficial to reduction of the cost of the subsequentconcentration evaporation.

TABLE 8 Content of obtained sodium sulfate corresponding to content ofsulfuric acid for acid activation Temperature/° C. 0 10 20 30 50 60 7080 90 100 Solubility 4.9 9.1 19.5 40.8 46.2 45.3 44.3 43.7 42.7 42.5Saturated mass 4.7% 8.3% 16.3% 29% 31.6% 31.2% 30.7% 30% 29.9% 29.8%fraction g/g

It can be seen from Table 8 that when the content of sulfuric acid is30%, the content of correspondingly produced sodium sulfate is 42.7%,and when the temperature of the ion resin in the production process iscontrolled at about 65° C., the saturated mass fraction of sodiumsulfate is 44.3% to 44.5%. Considering a fact that when a resin isactivated with sulfuric acid, the process of replacing sodium ions withH⁺ ions will be shortly suspended, causing a short-term increase of theconcentration of sodium sulfate in the activation process, and apossibility that sodium sulfate is precipitated to block the column,therefore, in the experiment, the content of sulfuric acid is adjustedto 15% to 25%. However, it is found from subsequent experiments thatwhen the concentration reaches 25%, sodium sulfate will be alsoprecipitated if the temperature is not well controlled, so the optimalsulfuric acid content is about 22%.

Based on the above analysis results, the resin column C or D ofComparative Example 10 was selected to undergo the following experiment.

3. Flowing of evaporated solution sample through column: an evaporatedsolution was diluted to a volume according to a certain ratio, a certainvolume of pre-treated resin was transferred into a chromatographiccolumn, the diluted evaporated solution flowed through the resin columnin a forward direction at a certain flow rate for adsorption, an endpoint was determined according to the requirements of different timeperiods, and various indicators were measured. After the flowing of theevaporated solution was completed, the resin column was washed withwater until a pH value of an output solution was 8 to 9, indicatingelution was completed.

4. Regeneration of resin: a sulfuric acid solution flowed through thecolumn in a forward direction at a certain flow rate for desorption, itwas determined that the resin was completely activated in response todetecting no sodium ion in the eluent, and then the resin column waswashed with water until a pH value of an output solution was greaterthan 4.

Experimental steps 3 and 4 were repeated, during which the conditions ofstep 3 were kept unchanged, and the content of the activating reagent ofstep 4 was changed. The conditions are shown in Table 9.

TABLE 9 Various parameters of complete activation of resin by acidicactivating reagent at different contents Batch Sulfuric acid Usagevolume Volume of water for number content of acid washing after acidactivation 1 4.7 wt %  22 L 6.5 L 2 9.8 wt %  20 L  7 L 3 12 wt % 17 L7.3 L 4 15 wt % 17 L 7.5 L 5 23 wt % 15 L 7.0 L 6 25 wt % 14 L 6.9 L

As shown in Table 9, under the same conditions, the total usage volumeof acid for activation is reduced as the acid content is increased. Inconjunction with the control analysis of sulfuric acid content, thecurrent data shows that the activation of the resin is relatively stableunder the sulfuric acid content of 23 wt %. After the acid activation,the usage volume of water for washing is first increased and thenreduced as the acid content is increased. As the acid content isincreased subsequently, the usage volume of acid is reduced, and theresin can be easily washed to pH 4 to 6. However, in the experiment,when the content is as high as 25 wt %, a small amount of solid will beprecipitated in the resin column if the temperature fluctuates,affecting the experiment. Therefore, taking the actual conditions intoconsideration, the sulfuric acid content is preferably 23 wt %.

Herein, description with reference to the terms “an embodiment”, “someembodiments”, “example”, “specific example” or “some examples”, etc.refers to that specific features, structures, materials orcharacteristics described in conjunction with the embodiment or exampleare included in at least one embodiment or example of the presentdisclosure. Herein, schematic representations of the above terms are notnecessarily directed to the same embodiment or example. Furthermore, thespecific features, structures, materials or characteristics describedmay be combined in any suitable manner in any one or more embodiments orexamples. In addition, those skilled in the art may combine andintegrate different embodiments or examples described herein, as well asfeatures of different embodiments or examples, without conflicting eachother.

While the embodiments of the present disclosure have been illustratedand described above, it should be understood that the above embodimentsare exemplary and are not construed as limiting the present disclosure.Those of ordinary skill in the art can make change, modification,replacement, and variation to the above embodiments within the scope ofthe present disclosure.

What is claimed is:
 1. A system for preparing taurine, comprising: asolution storage unit configured to store a solution containing alkalimetal taurinate, the solution being prepared by an ethylene oxideprocess; an ion exchange unit comprising plurality of ion exchange resincolumns each configured to be activated independently by a firstactivation manner or a second activation manner, the first activationmanner using sulfurous acid for activation, and the second activationmanner using sulfuric acid for activation, wherein each of the pluralityof ion exchange resin columns is a weakly acidic cation resin columnhaving an acidity higher than that of taurine; and a dispensing unitconnected to the solution storage unit and the ion exchange unit, thedispensing unit being configured to adjust an amount of the solutionconveyed from the solution storage unit to each of the plurality of ionexchange resin columns in the ion exchange unit, and the dispensing unitbeing further configured to: dispense a part of the solution containingthe alkali metal taurinate to at least one of the plurality of ionexchange resin columns treated by the first activation manner to obtainalkali metal bisulfite and taurine; and dispense the other part of thesolution containing the alkali metal taurinate to at least one of theplurality of ion exchange resin columns treated by the second activationmanner to obtain alkali metal sulfate and taurine.
 2. The systemaccording to claim 1, further comprising an activating solution changeunit connected to each of the plurality of ion exchange resin columnsand configured to change an activating solution for activating theplurality of ion exchange resin columns, and change an activation mannerof the at least one of the plurality of ion exchange resin columns fromthe first activation manner to the second activation manner or from thesecond activation manner to the first activation manner.
 3. The systemaccording to claim 2, further comprising an alkali metal ionconcentration detection module connected to an inlet and an outlet ofeach of the plurality of ion exchange resin columns, wherein the alkalimetal ion concentration detection module is adapted to independentlydetect a concentration of alkali metal ions in an input solution of eachof the plurality of ion exchange resin columns and a concentration ofalkali metal ions in an output solution of each of the plurality of ionexchange resin columns, wherein both the input solution and the outputsolution contain alkali metal taurinate, and wherein the alkali metalion concentration detection module is connected to the activatingsolution change unit to allow the activating solution change unit tochange the activation manner of the at least one of the plurality of ionexchange resin columns from the first activation manner to the secondactivation manner or from the second activation manner to the firstactivation manner based on a detection result of the alkali metal ionconcentration detection module.
 4. The system according to claim 1,wherein the dispensing unit is configured to adjust an amount of thesolution conveyed from the solution storage unit to each of theplurality of ion exchange resin columns independently, an amount of thesolution inputted into the at least one of the plurality of ion exchangeresin columns treated by the first activation manner is 60 wt % to 95 wt% of a total amount of the solution in the solution storage unit, and anamount of the solution inputted into the at least one of the pluralityof ion exchange resin columns treated by the second activation manner is5 wt % to 40 wt % of the total amount of the solution in the solutionstorage unit; optionally, a ratio of the amount of the solution inputtedinto the at least one of the plurality of ion exchange resin columnstreated by the first activation manner to the amount of the solutioninputted into the at least one of the plurality of ion exchange resincolumns treated by the second activation manner ranges from (3:2) to(19:1).
 5. The system according to claim 3, wherein the activatingsolution change unit is configured to: change, in response to theconcentration of alkali metal ions in the output solution of the atleast one of the plurality of ion exchange resin columns that is beingtreated by the first activation manner being greater than 60% of theconcentration of alkali metal ions in the input solution of the at leastone of the plurality of ion exchange resin columns, the activationmanner of the at least one of the plurality of ion exchange resincolumns to the second activation manner, and change, in response to theconcentration of alkali metal ions in the output solution being smallerthan or equal to 5% of the concentration of alkali metal ions in theinput solution, the activation manner of the at least one of theplurality of ion exchange resin columns to the first activation manner.6. The system according to claim 5, further comprising a solutionallocation module connected to a bottom of each of the plurality of ionexchange resin columns, wherein the solution allocation module isconfigured to: input an alkali metal bisulfite solution into the atleast one of the plurality of ion exchange resin columns from bottom totop before the at least one of the plurality of ion exchange resincolumns is treated by the first activation manner; and input an alkalimetal sulfate solution into the at least one of the plurality of ionexchange resin columns from bottom to top before the at least one of theplurality of ion exchange resin columns is treated by the secondactivation manner.
 7. The system according to claim 5, wherein thesecond activation manner is adapted for a second activation treatmentusing sulfuric acid at a concentration smaller than or equal to 25 wt %.8. The system according to claim 7, wherein the second activation manneris adapted for a second activation treatment using sulfuric acid at aconcentration smaller than or equal to 23 wt %.
 9. The system accordingto claim 5, wherein the sulfurous acid used by the first activationmanner is obtained by dissolving sulfur dioxide in an alkali metalbisulfite solution, the alkali metal bisulfite solution having aconcentration from 25 wt % to 50 wt %.
 10. The system according to claim1, further comprising: a reaction unit connected to the solution storageunit and configured to prepare an evaporated solution containing thealkali metal taurinate by the ethylene oxide process; and an alkalimetal bisulfite pipeline connected to the ion exchange unit and thereaction unit respectively, and configured to return the alkali metalbisulfite to the reaction unit.
 11. A method for preparing taurine,comprising: preparing an evaporated solution containing alkali metaltaurinate by an ethylene oxide process in a reaction unit; independentlytreating each of a plurality of ion exchange resin columns in an ionexchange unit by a first activation manner or a second activationmanner; dispensing a part of the evaporated solution containing thealkali metal taurinate to the at least one of the plurality of ionexchange resin columns treated by the first activation manner to obtainalkali metal bisulfite and taurine, and inputting the alkali metalbisulfite into the reaction unit; and dispensing the other part of theevaporated solution containing the alkali metal taurinate to at leastone of the plurality of ion exchange resin columns treated by the secondactivation manner to obtain alkali metal sulfate and taurine.
 12. Themethod according to claim 11, wherein the first activation mannerfurther comprises: passing alkali metal bisulfite through the at leastone of the plurality of ion exchange resin columns from bottom to top;dissolving sulfur dioxide in an alkali metal bisulfite solution toobtain a sulfurous acid solution; and passing the sulfurous acidsolution through the at least one of the plurality of ion exchange resincolumns from top to bottom to treat the at least one of the plurality ofion exchange resin columns by the first activation manner.
 13. Themethod according to claim 11, wherein the second activation mannerfurther comprises: passing an alkali metal sulfate solution through theat least one of the plurality of ion exchange resin columns from bottomto top; and passing a sulfuric acid solution having a concentrationsmaller than or equal to 25 wt % through the at least one of theplurality of ion exchange resin columns from top to bottom to treat theat least one of the plurality of ion exchange resin columns by thesecond activation manner.
 14. The method according to claim 11, furthercomprising: dispensing 60 wt % to 95 wt % of the evaporated solutioncontaining the alkali metal taurinate to the at least one of theplurality of ion exchange resin columns treated by the first activationmanner; and dispensing 5 wt % to 40 wt % of the evaporated solutioncontaining the alkali metal taurinate to the at least one of theplurality of ion exchange resin columns treated by the second activationmanner, optionally, a ratio of the evaporated solution dispensed to theat least one of the plurality of ion exchange resin columns treated bythe first activation manner to the evaporated solution dispensed to theat least one of the plurality of ion exchange resin columns treated bythe second activation manner ranges from (3:2) to (19:1).
 15. The methodaccording to claim 14, comprising, prior to activation: independentlydetermining a concentration of alkali metal ions in an input solution ofeach of the plurality of ion exchange resin columns and a concentrationof alkali metal ions in the at least one of the plurality of ionexchange resin columns to determine an activation manner of theactivation to be performed on the at least one of the plurality of ionexchange resin columns, wherein the input solution and an outputsolution contain alkali metal taurinate ions.
 16. The method accordingto claim 15, comprising: changing, in response to the concentration ofalkali metal ions in the output solution of the at least one of theplurality of ion exchange resin columns that is being treated by thefirst activation manner being greater than or equal to 60% of theconcentration of alkali metal ions in the input solution of the at leastone of the plurality of ion exchange resin columns, the activationmanner of the at least one of the plurality of ion exchange resincolumns to the second activation manner, and changing, in response tothe concentration of alkali metal ions in the output solution beingsmaller than or equal to 5% of the concentration of alkali metal ions inthe input solution, the activation manner of the at least one of theplurality of ion exchange resin columns to the first activation manner.17. The method according to claim 11, wherein a concentration of thealkali metal bisulfite ranges from 30 wt % to 40 wt %.
 18. The methodaccording to claim 17, wherein the concentration of the alkali metalbisulfite is 35 wt %.
 19. The method according to claim 13, wherein aconcentration of the alkali metal sulfate ranges from 2 wt % to 15 wt %.20. The method according to claim 19, wherein the concentration of thealkali metal sulfate ranges from 5 wt % to 10 wt %.